Folks did just that. How did you think other servers filled up on day 2? Serves that came up day 1 were “full” yesterday. People DID listen and move.
The 2nd problem is that the population rating is for ONLINE only - not total pop. So you could have had plenty of folks making new toons during the morning when it was low and empty, trying to log in in the evening only to be met with a full server.
Pay attention. Last night all but 4 were full. The only ones not full were the ones going up yesterday.